The Ukrainan navy has restarted special training for dolphins and other animals for military duties including attacking enemy combat swimmers and detecting mines, a military source in the Ukrainian naval port of Sevastopol told RIA Novosti on Thursday. "Ten dolphins are now being trained for special tasks in the Ukrainian state oceanarium, and the Ukrainian military are regularly training the animals for detecting things on the seabed," the source said. Dolphins were trained at Sevastopol for the Soviet Navy as far back as 1973. They were trained to find military equipment such as sea mines on the seabed as well as attacking divers and even carrying explosives on their heads to plant on enemy ships. After the breakup of the USSR and division of the Black Sea Fleet into Ukrainian and Russian fleets, the dolphin training section and its specialists were given to the Ukrainian Navy. They were then used for civilian tasks such as working with disabled children, in order to keep the unit intact. The killer-dolphins will be trained to attack enemy combat swimmers using special knives or pistols fixed to their heads, the source said. "We are now planning training exercises for counter-combat swimmer tasks in order to defend ships in port and on raids," he said. Their tasks also include patrolling stretches of water and detecting items of military interest and then marking them by attaching floating buoys. Several exercises have already been carried out this year with the dolphins in finding underwater weapons, both in the aquarium and outside it. "The mission was successfully carried out. Our dolphins found the items and attached devices to them which were fixed on their heads, after which a buoy on it was sent to the surface to mark it," the source said. The Ukrainian dolphin base is one of only two in the world, the other being in San Diego, California. There is no information on whether the Russian Navy has a similar unit.